For my senior project in mechanical engineering, I sought to create a novel, proof-of-concept 3D printer. I was inspired by a personal fascination for the conversion between two and three dimensions and a belief that 3D printing is a significant part of the future of fabrication. Spray foam is an inherently cheap and lightweight material, well-suited for model building and quick prototyping. To get from CAD to foam, the printer uses a four degree-of-freedom robot arm for travel, which is controlled by the V+ language.

The hardware portion of this project consisted of designing the actuation system and mounting plate for a purchased spray-foam gun. The entire system is self-contained and attached to the end-effector of the robot arm.

I chose a pneumatic system for actuation, mostly because I had never used one before. A custom-made housing and holds the pneumatic cylinder to the gun, which pushes against the trigger with a nylon ball when actuated. A screw at the opposite end acts as an adjustable hard-stop.

The pneumatic cylinder is driven by an in-room air line attached to a solenoid valve, which is controlled by a small circuit connected to the robot arm’s controller. I communicated with the valve directly through the robot’s OS with the program codes I wrote.

The hardest part of this project was the software side. I was learning a programming language for the first time and went through many trials of translating a CAD model into reality and fine-tuning my program codes.

A test print of a 3D object. While not an exact replica, this project was ultimately about trying new things – whether learning how to use pneumatic systems, writing code for the first time, or challenging myself to develop a new 3D printing method.